The structure of a micro-electro-mechanical system (MEMS) thermal sensor and a method of fabricating the MEMS thermal sensor are disclosed. A method of fabricating a MEMS thermal sensor includes forming first and second sensing electrodes with first and second electrode fingers, respectively, on a substrate and forming a patterned layer with a rectangular cross-section between a pair of the first electrode fingers. The first and second electrode fingers are formed in an interdigitated configuration and suspended above the substrate. The method further includes modifying the patterned layer to have a curved cross-section between the pair of the first electrode fingers, forming a curved sensing element on the modified patterned layer to couple to the pair of the first electrodes, and removing the modified patterned layer.

A microelectromechanical system (MEMS) device includes a substrate and a movable element at least partially suspended above the substrate and having at least one degree of freedom. The MEMS device further includes a protrusion extending from the substrate and configured to contact the movable element when the movable element moves in the at least one degree of freedom, wherein the protrusion comprises a surface having a water contact angle of higher than about 15° measured in air.

The structure of a micro-electro-mechanical system (MEMS) thermal sensor and a method of fabricating the MEMS thermal sensor are disclosed. A method of fabricating a MEMS thermal sensor includes forming first and second sensing electrodes with first and second electrode fingers, respectively, on a substrate and forming a patterned layer with a rectangular cross-section between a pair of the first electrode fingers. The first and second electrode fingers are formed in an interdigitated configuration and suspended above the substrate. The method further includes modifying the patterned layer to have a curved cross-section between the pair of the first electrode fingers, forming a curved sensing element on the modified patterned layer to couple to the pair of the first electrodes, and removing the modified patterned layer.

A semiconductor device includes a substrate, a movable portion provided on the substrate, a junction frame provided on the substrate to surround the movable portion, a cap bonded to the junction frame, the cap having a recessed portion and covering a space over the movable portion with the recessed portion facing the movable portion, the cap having an inside wall provided with irregularities, and a prevention film formed on the inside wall of the cap, the prevention film having irregularities on a surface thereof.

An inertial sensor includes a substrate, a movable element that swings around a swing axis; and a protrusion that overlaps with the movable element in the plan view and protrudes from the substrate toward the movable element. The protrusion includes a first protrusion and a second protrusion so located as to be farther from the swing axis than the first protrusion, and when the movable element swings relative to the substrate around the swing axis, the first protrusion and the second protrusion come into contact with the movable element at the same time or the first protrusion comes into contact with the movable element and then the second protrusion comes into contact with the movable element.

The present invention provides a substrate that is highly resistant to ESD, on which a reverse sound hole type MEMS microphone can be mounted. The substrate has one surface connected to a MEMS microphone, and comprises a substrate sound hole that penetrates through the substrate and communicates with a sound hole of the MEMS microphone, and a GND pad disposed around the substrate sound hole on another surface of the substrate.

A physical quantity sensor includes a movable body, a support portion supporting the movable body through a connecting portion, and a substrate that is disposed so as to overlap the movable body in plan view and provided with a first fixed electrode and a second fixed electrode along a first direction orthogonal to a longitudinal direction of the connecting portion. In plan view, a dummy electrode that is disposed next to the first fixed electrode and is at the same potential as the movable body is provided on the substrate. The first fixed electrode and the dummy electrode includes a first electrode material layer provided on the substrate, and a second electrode material layer provided on the substrate and on the first electrode material layer. The second electrode material layer constituting the first fixed electrode and the second electrode material layer constituting the dummy electrode are provided between the first electrode material layer constituting the first fixed electrode and the first electrode material layer constituting the dummy electrode, in plan view. A distance between the second electrode material layer constituting the first fixed electrode and the second electrode material layer constituting the dummy electrode is smaller than a distance between the first electrode material layer constituting the first fixed electrode and the first electrode material layer constituting the dummy electrode, in plan view.

Provided are a method for preparing a silicon wafer with a rough surface and a silicon wafer, which solves the problem in the prior art that viscous force is likely to be generated. The method includes: depositing a first film layer having a large surface roughness on a surface of a silicon wafer that has been subjected to planar planarization, and then blanket etching the first film layer to remove the first film layer. Then, the surface of the first silicon layer facing away from the substrate is further etched to form grooves and protrusions, which provide roughness, thereby forming a silicon wafer with a rough surface. When the silicon wafer approaches to another film layer, the viscous force generated therebetween is reduced, and thus the sensitivity of the MEMS device is improved and the probability of out-of-work MEMS device is reduced.

Provided are a method for preparing a silicon wafer with a rough surface and a silicon wafer, which solves the problem in the prior art that viscous force is likely to be generated. The method includes: depositing a first film layer having a large surface roughness on a surface of a silicon wafer that has been subjected to planar planarization, and then blanket etching the first film layer to remove the first film layer. Then, the surface of the first silicon layer facing away from the substrate is further etched to form grooves and protrusions, which provide roughness, thereby forming a silicon wafer with a rough surface. When the silicon wafer approaches to another film layer, the viscous force generated therebetween is reduced, and thus the sensitivity of the MEMS device is improved and the probability of out-of-work MEMS device is reduced.

According to one embodiment, a MEMS element includes a base body, a supporter, a film part, a first electrode, a second electrode, and an insulating member. The supporter is fixed to the base body. The film part is separated from the base body in a first direction and supported by the supporter. The first electrode is fixed to the base body and provided between the base body and the film part. The second electrode is fixed to the film part and provided between the first electrode and the film part. The insulating member includes a first insulating region and a second insulating region. The first insulating region is provided between the first electrode and the second electrode. A first gap is provided between the first insulating region and the second electrode. The second insulating region does not overlap the first electrode in the first direction.